Applicator for molten adhesive



Feb. 11, 1964 J. 5. KAMBORIAN 3,

'APPLICATOR FOR MOLTEN ADHESIVE Filed April 6, 1960 w 6 4 {I f United States Patent 3,121,156 APPLICATOR FQR MOLTEN ADHESIVE Jacob S. Kamherian, 133 Forest Ave, West Newton, Mass. Filed Apr. 6, 1960, Ser. No. 20,461 11 Claims. (Cl. 219-21) This invention relates to applicators and particularly to an applicator for applying molten adhesive to parts of shoes, and has for its principal objects to provide a device for transferring molten adhesive from an apparatus containing a quantity of molten adhesive to the work to which it is to be applied without appreciable cooling during the period of transfer; to provide an applicator with which a substantial quantity of molten adhesive may be picked out of a container and transferred to the work to which it is to be applied without drip or run; to provide an applicator in which molten adhesive may be worked into narrow and/or limited spaces so as to spread the adhesive uniformly; and to provide an applicator whch may be kept hot over prolonged periods without correspondingly heating the handle, or damaging the applicator tip.

As herein illustrated, the applicator comprises a slender rigid rod having a handle at one end, an elongated flexible tip at the other end and a heating element disposed in the rod with one end adjacent the tip in heatconductive engagement therewith for heating the tip. Preferably the rod is hollow and a heat-conductive head is screwed to one end of it over a forwardly projecting portion of the heating element disposed in the rod, so that the head and heating element have intimate heatconductive contact. The tip in the preferred form is constituted by a steel spring wire wound around the head and forwardly thereof in the form of a hollow coil which is open at its forward end. A perforated nonconductive sleeve joins the rear end of the rod with a handle made of heat-insulative material.

The invention will now be described in greater detail with reference to the accompanying drawing wherein:

FIG. 1 is a longitudinal diametrical section of the applicator with a portion of the handle broken away; and

FIG. 2 is a view corresponding to FIG. 1, showing a cooling jet mounted thereon.

The applicator comprises a slender rigid rod which may be comprised of armetal such as iron and which contains axially of it a chamber 12. The rod has at its forward end an internally threaded opening 14- concentric with the chamber 12 and at its rear end an externally threaded boss 16. Thechamber 12 is adapted to receive a heating element 18 with a portion of it extending forwardly into the threaded opening 14. A passage 20 extends rearward-1y from the chamber 12 through the boss 16 to accommodate wiring for supplying current to the heating element.

A rigid elongate cylindrical head .22 having an externally threaded boss 24 and an axial opening 26 is screwed into the threaded opening 14 in the forward end of the rod 10, over the forwardly projecting end of the heating element 18, so as to be in intimate heat-conductive relation thereto. Preferably the head is of solid cross-section and is comprised of aluminum. A steel spring wire 28 is wound spirally about the head and forwardly thereof on itself to provide a hollow tip 30 of gradually decreasing diameter in a direction extending away from the head. The tip is open at its end and is yieldably flexible. The tip in axial section may assume the shape of a cone, a segment of a circle, or any other convenient shape.

A hollow perforated sleeve 32 of non-heat-conductive material is screwed onto the externally threaded boss 16 at the rear end of the rod 10 and has at its rear end an externally threaded boss .34 onto which is screwed a handle 36, the latter being comprised of pressed fibers which are resistant to heat transfer. The perforations in the sleeve 32 permit passage of air through this section so as to conduct heat away from the handle.

The flexible heated tip will maintain adhesive picked up on the tip from a container of liquid during the period of transfer from the container to the work and will serve, by reason of its flexibility, to spread and rub the adhesive over narrow areas and into confined places.

The tip made of a hollow coil of spring wire of gradually decreasing diameter has the advantage of standing up to the high temperatures of the adhesive carried thereby, such temperatures usually ranging from 290' degrees Fahrenheit to 500 degrees Fahrenheit. When the applicator picks up liquid adhesive from a container, said liquid will be retained both on the inside and the outside of the wire forming the applicator tip and will also be retained in the reservoir formed by the hollow 37 within the tip 30. When the applicator tip is rubbed against the work, the coil convolutions will flex and spread apart thus allowing adhesive on the exterior and interior surfaces of the tip and adhesive within hollow 37 to be deposited on the work.

The gradually diminishing diameter of the coil conyolutions will enable a line contact to take place between the exterior surface of the tip and the work thus providing for a larger surface of the work contacted by the tip than would be the case if the tip were of uniform diameter. That is to say, when the applicator is held inclined to the surface of the work while it is rubbed therealon-g all of the downwardly facing portions of the tip will be in substantial contact with the work.

It is to be understood that the advantages of providing the tip with a gradually decreasing diameter will accrue if the tip is made of any material that has a limited flexibility but sufiicient rigidity so as to preclude a substantial deformation or squashing of the tip when it is rubbed along the work. The tip could, for example, be made of a solid or hollow block of a suitable heat resistant rubber or plastic, such as silicone rubber or Teflon and have the cited advantages.

It is sometimes desirable to cool the molten adhesive as rapidly as it is applied in order to quickly set the adhesive or render it tacky so that parts which are to be bonded by the adhesive will more readily adhere to each other. Accordingly, a nozzle 38- (FIG. 2) is mounted on the rod It) by means of a clamp 40 so as to be parallel to the axis of the rod with its tip 42 close to the applicator head 22. The rear end of the nozzle is connected to a flexible conductor 44, by means of which cooling air may be supplied to the nozzle under pressure. With this arrangement, when the operator rubs the applicator tip along the surface of the work to deposit molten adhesive thereon, the adhesive will be cooled as it is deposited.

The applicator herein shown is particularly effective for applying adhesive to the marginal portions of insoles preparatory to end lasting operations and is especially effective when used in conjunction with the adhesive melting apparatus shown in the pending application Serial No. 20,460, filed April 6, 1960. The applicator also finds particular utility in carrying out the method disclosed in pending application Serial No. 28 408 filed May 11, 1960-, now Patent No. 3,050,756.

t should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which fall within the scope of the appended claims.

I claim:

1. An adhesive applicator comprising an elongated rod-like member, a handle at the rear end of the member, an applicator element at the forward end of the member, heating means positioned interiorly of the member for maintaining the adhesive retained by the applicator element above ambient temperature, a nozzle so mounted on the member as to direct cooling fluid that is below the said temperature of the adhesive forwardly of the member, and means for connecting said nozzle to a source of said fluid under pressure.

2. -An applicator comprising a slender rigid rod having a handle at one end, a helical coil of wire at the opposite end that extends forwardly of said opposite end and forms an empty, hollow tip, and a heating element disposed in the rod with an end adjacent the coil of wire to heat the same.

3. An adhesive applicator, as defined in claim 2, wherein the tip is of gradually decreasing diameter in a direction extending away from the rod.

4. An applicator comprising a slender rigid rod having a handle at one end, an empty, hollow, flexible applicator tip made of a helically wound coil of wire at the opposite end that extends forwardly of said opposite end, said tip having a gradually diminishing diameter in a direction extending away from the rod, a heating element disposed in the rod adjacent the tip to heat the same, and means between the heating element and handle to lessen the transfer of heat from the heating element to the handle.

5. An applicator comprising a slender hollow rod, a heating element disposed in the rod, a conductor head fixed to one end of the rod so as to be in conductive engagement with the heating element, a flexible coil of wire wound on the conductor head that extends forwardly of the head and forms an empty, hollow tip, a handle, and a non-conductive sleeve joining the handle to the other end of the hollow rod.

6. An applicator comprising a slender hollow metal rod containing an internally threaded opening at one 7 end and an externally threaded boss at the other end, a

heating element disposed in the rod with an end projecting into the opening, a heat-conductive head of solid cross-section having an externally threaded boss adapted to be screwed into the opening in the rod, and an axial opening for receiving the forwardly extending end of the heating element in heat-conductive relation thereto, a spring steel wire wound about the head and extending (forwardly thereof in the form of a spring coil of gradually decreasing diameter in a direction extending away from the head, a perforated non-conductive, heat conducting sleeve having an internally threaded portion at one end adapted to be screwed onto the boss at the rear end of the rod, an externally screw-threaded boss at its opposite end for threaded engagement with the handle,

and a handle of heat-insulative material screwed onto the boss.

7. An adhesive applicator comprising an elongated rod-like member, a handle at the rear end of the member, an applicator tip at the fonward end of the member, said tip comprising a flexible coil or wire of gradually diminishing diameter in a direction extending away from the member, heating means positioned interiorly of the member for maintaining the adhesive retained by the applicator element above ambient temperature, a nozzle so mounted on the member as to direct cooling fluid that is below the said temperature of the adhesive forwardly of the member, and means for connecting said nozzle to a source of said fluid under pressure.

8. An applicator comprising: an elongate member; a coil of wire secured to the forward end of the member that extends spirally. forwardly thereof and forms an empty, hollow tip; and heating means located within the member.

9. An applicator comprising: an elongate rod; a head secured to the forward end of the rod; a coil of wire wound on the head that extends spirally forwardly thereof and forms an empty, hollow tip; and a heating element located within the rod and head.

'10. An applicator comprising: an elongate rod having a chamber located on its axis and intersecting the forward end of the rod; a head secured to the forward end of the rod having a chamber in alignment with the rod chamber and intersecting the rearward end of the head; a heating element located in said chambers; and a coil of wire wound on the head that extends spirally forwardly thereof and forms an empty, hollow tip.

11. An applicator comprising: a rod; a head of heatconductive material secured to the forward end of the rod; a heating element located in aligned chambers in the rod and head; a hollow perforated sleeve of thermally insulative material secured to the rear end of the rod; and a coil of wire extending spirally and forwardly of the head and forming an empty, hollow tip.

References Cited in the file of this patent UNITED STATES PATENTS 399,387 Dolan Mar. 12, 1889 781,250 Welch Jan. 31, 1905 1,047,021 Farnum Dec. 10, 1912 1,238,671 Holcomb Aug. 28, 1917 1,253,032 Hardin Jan. 8, 1918 1,836,342 'Siptrott Dec. 15, 11931 1,905,987 Lane a Apr. 25, 1933 2,243,549 Yocom May 27, 1941 2,647,065 Scholl July 28, 1953 2,761,946 Brons-tein Sept. 4, 1956 2,791,669 Ferrara May 7, 1957 2,837,756 Barlow et al. June 10, 1958 2,975,467 Stanzel Mar. 21, 196 1 

2. AN APPLICATOR COMPRISINGG A SLENDER RIGID ROD HAVING A HANDLE AT ONE END, A HELICAL COIL OF WIRE AT THE OPPOSITE END THAT EXTENDS FORWARDLY OF SAID OPPOSITE END AND FORMS AN EMPTY, HOLLOW TIP, AND A HEATING ELEMENT DISPOSED IN THE ROD WITH AN END ADJACENT THE COIL OF WIRE TO HEAT THE SAME. 